1. Field of the Invention
The present invention relates to an antenna structure, and more particularly, to an antenna structure for surrounding a first radiator with a second radiator, such that there are a plurality of predetermined gaps existed in between first side edges of the first radiator and second side edges of the second radiator to form coupling effects.
2. Description of the Prior Art
As wireless telecommunication develops with the trend of micro-sized mobile communication products, the location and the space arranged for antennas are limited. Therefore, some built-in micro antennas have been developed. Currently, micro antennas such as chip antennas, planar antennas etc are commonly used. All these antennas have the feature of small volume. The planar antenna has the advantages of small size, light weight, ease of manufacturing, low cost, high reliability, and can also be attached to the surface of any object. Therefore, micro-strip antennas and printed antennas are widely used in wireless communication systems.
Hence, how to improve antenna efficiency, adjust impedance matching, improve radiation patterns, and increase bandwidths of the antennas have become important topics in this field.